The present invention relates to an arrangement for mounting a rotary shaft on a stationary support. The arrangement is especially suitable for mounting of a governor shaft to a case of an automatic transmission of an automobile.
A governor is driven by a rotating member of a transmission, and produces a governor fluid pressure which varies in relation with vehicle speed. A governor shaft transmits rotation from the rotating member of the transmission to a governor valve assembly. The governor shaft is usually formed with an annular groove. A stopper pin is inserted through the transmission case from the outside, and engaged with the annular groove of the governor shaft in order to prevent the governor shaft from being axially extracted. The stopper pin allows the governor shaft to rotate but prevents the governor shaft from moving axially out of position. Usually, the stopper pin has a cylindrical shape, so that the stopper pin makes contact with the annular groove of the governor shaft along a line. Along this line of contact, load is localized, and wear between the stopper pin and the rotating governor shaft is accelerated. Therefore, the stopper pin is liable to break because of severe wear caused during a long period of use.